<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title></title>
    <style>
       * {
         font-size: 20px;
       }
    </style>
  </head>
  <body>
    <div id="content1">
      content1
      <div>child1</div>
      <div>child2</div>
    </div>

    <div id="content2">
      content2
      <div>child1</div>
      <div>child2</div>
    </div>
  </body>
</html>
